Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Distribution of tobacco streak, tomato ringspot, and raspberry bushy dwarf viruses in Rubus ursinus and R. leucodermis collected from the Pacific Northwest.

Abstract

Clonal and seed propagules of R. ursinus (trailing blackberry) and seed of R. leucodermis (western black raspberry) were collected from the Pacific Northwest (Oregon and Washington, USA and British Columbia, Canada) in 4 general environmental regions. These were at sea level along the Pacific coast, in the coastal mountains adjacent to the coast, in the Willamette Valley and in the Cascade Mountains. After the propagules were established, leaves were tested by ELISA. None of the R. leucodermis samples tested positive for raspberry bushy dwarf idaeovirus (RBDV), tomato ringspot nepovirus (TomRV) or tobacco streak ilarvirus (TSV). R. leucodermis was either resistant to the viruses or their vectors, the viruses were not seed transmitted or the viruses were not detected due to inadequate sampling. No samples of R. ursinus tested positive for RBDV or TomRV. Samples from 77% of the sites where cuttings were taken and 37% of the seedling populations tested positive for TSV. Along the Pacific coast only 20% of the sites sampled by cuttings tested positive for TSV. The percentage of infected sites where cuttings were taken increased to 88 and 100% in the coastal mountains and the Cascade Mountains, respectively. On the Pacific coast, 14% of seedling sites tested positive for TSV. The number of TSV positive seedling sites increased to 45 and 36% in the Cascade Mountains and the coastal mountains, respectively. The Willamette Valley site tested negative for TSV. All except one of the low elevation sites tested negative for TSV. It is suggested that prevailing winds or earlier flowering may prevent some of these Pacific Coast populations from becoming infected. Many of the TSV positive sites had some samples that tested negative and it is concluded that TSV is unevenly distributed within these populations.